A sealing gasket

Abstract

The present invention discloses a sealing gasket, which includes a first ring and a second ring coaxially stacked, and a stress relief ring welded and fixed between the inner circumferential portions of the first ring and the inner circumferential portion of the second ring. The longitudinal section of the stress relief ring is in a C shape. When the sealing gasket is used in a sealing device, when there is a radial displacement difference between the flanges on both sides of the sealing gasket due to different working temperature fields, the first ring and the second ring always maintain a seal through the deformation of the stress relief ring, so that the first sealing ring and the second sealing ring always move synchronously and contact relatively statically with the sealed surfaces they contact, without wear, so that the sealed surfaces do not rub against each other to damage the sealing ring, and further the seal remains effective.

Description

Technical Field

[0001] The present invention relates to the field of sealing, and particularly to a sealing gasket. Background Art

[0002] In fields such as nuclear power, petrochemical, and food, traditional flange seals mainly use double-cone ring gaskets, octagonal (elliptical) gaskets, metal ring gaskets, or metal wound gaskets, etc. Due to the different temperatures on both sides of the sealed connecting flange, the flanges on both sides of the sealant deform out of sync at different temperatures, resulting in a relative displacement difference in the radial direction of the flange sealing surface, posing a risk of damaging the sealant or reducing the sealing stress and causing seal failure. Summary of the Invention

[0003] The object of the present invention is to provide a sealing gasket to compensate for the relative displacement difference generated in the radial direction of the flange sealing surface and ensure the reliability of the seal.

[0004] To achieve the above object, the technical solution adopted by the present invention is: a sealing gasket, the sealing gasket includes a first ring and a second ring stacked coaxially, a first sealing ring is provided at the outer shaft end of the first ring, a second sealing ring is provided at the outer shaft end of the second ring, the sealing gasket further includes a stress release ring, the longitudinal section of the stress release ring is a C shape arched radially outward, a first arc-shaped groove is provided at the inner circumferential part of the first ring, a second arc-shaped groove is provided at the inner circumferential part of the second ring, the first arc-shaped groove and the second arc-shaped groove cooperate with each other to form a receiving space for receiving the stress release ring, both shaft ends of the stress release ring are welded and fixed to the first ring and the second ring respectively along the circumferential direction, and the outer circumferential surface of the stress release ring is arranged with a gap between the circumferential groove wall of the first arc-shaped groove.

[0005] Preferably, the outer circumferential surface of the stress release ring is in contact with the circumferential groove wall of the second arc-shaped groove.

[0006] Preferably, the gap between the outer circumferential surface of the stress release ring and the circumferential groove wall of the first arc-shaped groove is arranged to gradually increase from outside to inside along the axial direction of the first ring.

[0007] Preferably, among the inner shaft end of the first ring and the inner shaft end of the second ring, a ring-shaped boss is provided on one of them, a ring-shaped groove is provided on the other, the radial thickness of the ring-shaped boss is less than the radial width of the ring-shaped groove, and the ring-shaped boss is correspondingly inserted into the ring-shaped groove.

[0008] As a preferred embodiment, the ring-shaped boss is provided on the first ring, the ring-shaped groove is provided on the second ring, and the inner circumferential surface of the ring-shaped boss is arranged with a gap between the inner circumferential wall of the ring-shaped groove.

[0009] As another preferred embodiment, the annular groove is provided on the first ring, the annular boss is provided on the second ring, and there is a gap between the outer circumferential surface of the annular boss and the outer circumferential wall of the annular groove.

[0010] Furthermore, an inner sealing ring is also provided on the annular boss, and the inner sealing ring is sealingly connected to the bottom surface of the annular groove.

[0011] Preferably, the sealing gasket further includes a leak detection ring. The two axial end portions of the leak detection ring are respectively welded and fixed to the outer circumferential portion of the first ring and the outer circumferential portion of the second ring along the circumferential direction. A closed leak detection chamber is formed among the first ring, the second ring, the stress release ring and the leak detection ring. A leak guiding pipe communicating with the leak detection chamber is also connected to the leak detection ring.

[0012] Furthermore, the longitudinal section of the leak detection ring is convex or concave outward along the radial direction.

[0013] Furthermore, a first outer sealing ring is also provided at the outer axial end portion of the first ring. The first outer sealing ring is located radially outside the first sealing ring. A first leak detection hole penetrating axially is formed in the first ring, and the first leak detection hole is located radially between the first sealing ring and the first outer sealing ring; a second outer sealing ring is provided at the outer axial end portion of the second ring. The second outer sealing ring is located radially outside the second sealing ring. A second leak detection hole penetrating axially is formed in the second ring, and the second leak detection hole is located radially between the second sealing ring and the second outer sealing ring.

[0014] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: When the sealing gasket of the present invention is used in a sealing device, when there is a radial displacement difference between the flanges on both sides of the sealing gasket due to different working temperature fields, the deformation of the stress release ring can be used to always keep the first ring and the second ring sealed, so that the first sealing ring and the second sealing ring always move synchronously and contact relatively statically with the sealed surfaces they contact, without wear, and thus the sealed surfaces will not rub against each other to damage the sealing ring, and further the seal remains effective. This sealing gasket is particularly suitable for working conditions of high temperature and high pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Acc Figure 1 is a longitudinal sectional view of the sealing gasket according to Embodiment 1 of the present invention;

[0016] Acc Figure 2 is a longitudinal sectional view of the sealing device using the sealing gasket of Acc Figure 1 , where the sealing gasket is not yet compressed;

[0017] Appendix Figure 3 For the appendix Figure 2 is a longitudinal sectional schematic view when the sealing gasket in the sealing device is pressed and undergoes radial displacement;

[0018] Appendix Figure 4 is a longitudinal sectional schematic view of the sealing gasket of Embodiment 2 of the present invention;

[0019] Appendix Figure 5 For the sealing device using the appendix Figure 4 is a longitudinal sectional schematic view of the sealing device with the sealing gasket, where the sealing gasket is pressed and has not undergone radial displacement;

[0020] Appendix Figure 6 is a longitudinal sectional schematic view of the sealing gasket of Embodiment 3 of the present invention;

[0021] Appendix Figure 7 is a longitudinal sectional schematic view of the sealing gasket of Embodiment 4 of the present invention;

[0022] Appendix Figure 8 For the sealing device using the appendix Figure 7 is a longitudinal sectional schematic view of the sealing device with the sealing gasket, where the sealing gasket is pressed and has not undergone radial displacement;

[0023] Appendix Figure 9 is a longitudinal sectional schematic view of the sealing gasket of Embodiment 5 of the present invention;

[0024] Appendix Figure 10 For the sealing device using the appendix Figure 9 is a longitudinal sectional schematic view of the sealing device with the sealing gasket, where the sealing gasket is pressed and has not undergone radial displacement;

[0025] Wherein: 100, the first flange; 101, the first flange surface; 102, the first installation groove;

[0026] 200, the second flange; 201, the second flange surface; 202, the second installation groove;

[0027] 300, the sealing gasket; 1, the first ring; 11, the annular boss; 12, the annular groove; 13, the first leak detection hole; 14, the first arc-shaped groove; 2, the second ring; 21, the annular groove; 22, the second leak detection hole; 3, the first sealing ring; 4, the second sealing ring; 5, the stress release ring; 6, 6', the leak detection ring; 7, the leak guiding pipe; 8, the inner sealing ring; 9, the first outer sealing ring; 10, the second outer sealing ring. Detailed implementation manners

[0028] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0029] Embodiment 1

[0030] SeeFigure 1 The shown gasket includes a first ring 1 and a second ring 2 which are coaxially stacked. A first sealing ring 3 is provided at the outer shaft end of the first ring 1, and a second sealing ring 4 is provided at the outer shaft end of the second ring 2. The first sealing ring 3 and the second sealing ring 4 can be made of metal or non-metal materials, specifically, they can be metal rings, packing rings, O-rings, etc. The gasket realizes the sealed connection with the flange surfaces of two flanges through the first sealing ring 3 and the second sealing ring 4. Here, the shaft ends where the first ring 1, the second ring 2 are in fit connection with the flange are called outer shaft ends, and the shaft ends where the first ring 1 and the second ring 2 are in contact with each other are called inner shaft ends.

[0031] The gasket further includes a stress relief ring 5. The longitudinal section of the stress relief ring 5 is in a C shape arched radially outward, and its outer circumferential surface is an arc surface. The stress relief ring 5 is coaxially arranged with the first ring 1 and the second ring 2, and the inner diameters of the three are the same. A first arc-shaped groove 14 is provided at the inner circumferential part of the first ring 1, and a second arc-shaped groove (not marked in the figure) is provided at the inner circumferential part of the second ring 2. The above-mentioned first arc-shaped groove 14 and the second arc-shaped groove are both semi-circular arc grooves, and the two cooperate with each other to form a receiving space for receiving the stress relief ring 5. The two shaft ends of the stress relief ring 5 are respectively welded and fixed to the first ring 1 and the second ring 2 along the circumferential direction, so that the gap between the first ring 1 and the second ring 2 is closed at the inner circumferential part by the stress relief ring 5.

[0032] The outer circumferential surface of the stress relief ring 5 is arranged with a gap from the circumferential groove wall of the first arc-shaped groove 14, and this gap is as shown at A in Figure 1 . As a preferred method, this gap is arranged to gradually increase from outside to inside along the axial direction of the first ring 1. The outer circumferential surface of the stress relief ring 5 is arranged in contact with the circumferential groove wall of the second arc-shaped groove. In this way, when the second ring 2 has a displacement difference relative to the first ring 1 radially outward, the stress relief ring 5 deforms. One shaft end of the stress relief ring 5 abuts against the second arc-shaped groove and can bear a higher pressure, and the other shaft end deforms, and the above-mentioned gap provides a space for the stress relief ring 5 to deform and release.

[0033] See Figure 1 As shown, in this embodiment, a ring-shaped boss 11 is provided on the inner shaft end of the first ring 1, and a ring-shaped groove 21 is provided on the inner shaft end of the second ring 2. The radial thickness of the ring-shaped boss 11 is less than the radial width of the ring-shaped groove 21, and the above-mentioned ring-shaped boss 11 is correspondingly inserted into the ring-shaped groove 21, as shown at Figure 1At position B in the figure, there is a gap between the annular boss 11 and the annular groove 21, which enables the annular boss 11 to move in the annular groove 21 when the second ring 2 has a displacement difference relative to the first ring 1 in the radial outward direction. That is, a radial deformation compensation space is reserved when the second ring 2 has a displacement difference relative to the first ring 1 in the radial direction. When setting, in the unused state of the sealing gasket, it is only necessary to ensure that there is a gap between the inner circumferential surface of the annular boss 11 and the inner circumferential wall of the annular groove 21. This gap should not be less than the displacement difference between the second ring 2 and the first ring 1 in the radial direction. When specifically setting, the above gap value is determined according to multiple factors such as the material used for the sealing gasket and the working condition environment. In some other embodiments, the annular groove can also be provided on the first ring 1 and the annular boss can be provided on the second ring 2. At this time, it is necessary to ensure that there is a gap between the outer circumferential surface of the annular boss and the outer circumferential wall of the annular groove.

[0034] In this embodiment, the height of the annular boss 11 is greater than the depth of the annular groove 21, so that there is a gap between the inner axial end face of the first ring 1 and the inner axial end face of the second ring 2.

[0035] See Figure 2 、 Figure 3 The shown sealing device includes a first flange 100 having a first flange surface 101, a second flange 200 having a second flange surface 201, and a sealing gasket 300 for sealing connection between the first flange surface 101 and the second flange surface 201. A first mounting groove 102 is provided on the first flange 100, and a second mounting groove 202 is provided on the second flange 200.

[0036] The first flange 100, the second flange 200, and the sealing gasket 300 are coaxially arranged, and the working temperature field of the second flange 200 is higher than that of the first flange 100. The first flange 100 and the second flange 200 are axially pressed and connected by bolts. The sealing gasket 300 is pressed between the first flange 100 and the second flange 200. Among them, the outer axial end of the first ring 1 is fittingly embedded in the first mounting groove 102, the outer axial end of the second ring 2 is fittingly embedded in the second mounting groove 202, a seal is formed between the first sealing ring 3 and the bottom wall of the first mounting groove 102, and a seal is formed between the second sealing ring 4 and the bottom wall of the second mounting groove 202.

[0037] After the sealing gasket 300 is pressed, the first ring 1 and the second ring 2 are respectively positioned and constrained in the first mounting groove 102 and the second mounting groove 202. The axial outer end faces of the first ring 1 and the second ring 2 are respectively in bearing contact with the flange surfaces of the two flanges, restricting the compression amounts of the first sealing ring 3 and the second sealing ring 4, so that the sealing stresses of each sealing ring are constant.

[0038] When the sealing device is in the working state and there is a radial displacement difference between the flanges on both sides of the sealing gasket 300 due to a temperature difference, the first installation groove 102 and the second installation groove 202 move non-synchronously along the radial direction, and the displacement difference between the two is as shown in Figure 3 a shown in the figure. At this time, the deformation of the stress release ring 5 can be used to always maintain the seal between the first ring 1 and the second ring 2. The first ring 1 on the low-temperature side is constrained in the first installation groove 102 and moves radially with the first flange 100, and the second ring 2 on the high-temperature side is constrained in the second installation groove 202 and moves radially with the second flange 200. Thus, the first sealing ring 3 and the second sealing ring 4 always move synchronously and are relatively stationary in contact with the sealed surfaces they contact, without wear, so that the sealed surfaces do not rub against each other and damage the sealing ring, and further the seal remains effective. The sealing gasket of this embodiment is particularly suitable for working conditions of high temperature and high pressure.

[0039] Embodiment 2

[0040] See Figure 4 the shown sealing gasket. The main difference compared with the sealing gasket of Embodiment 1 is that in this embodiment, the sealing gasket further includes a leak detection ring 6. Here, the longitudinal section of the leak detection ring 6 is a C shape protruding outward. The two shaft ends of the leak detection ring 6 are respectively welded and fixed to the outer circumferential part of the first ring 1 and the outer circumferential part of the second ring 2 along the circumferential direction. A closed leak detection chamber is formed among the first ring 1, the second ring 2, the stress release ring 5 and the leak detection ring 6. A leak guide pipe 7 communicating with the above leak detection chamber is also fixedly connected to the leak detection ring 6. In this way, the weld of the stress release ring 5 can be inspected for leakage, so as to give an alarm in time when the weld fails. The sealing device using this sealing gasket is as shown in Figure 5 the figure.

[0041] Embodiment 3

[0042] See Figure 6 the shown sealing gasket. The main difference compared with the sealing gasket of Embodiment 2 is that in this embodiment, the longitudinal section of the leak detection ring 6' in the sealing gasket is a C shape concave inward.

[0043] Embodiment 4

[0044] See Figure 7 the shown sealing gasket. The main difference compared with the sealing gasket of Embodiment 2 is that in this embodiment, an annular groove 12 is further formed on the annular boss 11, and an inner sealing ring 8 is arranged in the annular groove 12, and the inner sealing ring 8 is hermetically connected to the bottom surface of the annular groove 21. In this way, once the weld at the stress release ring 5 fails, a second sealing barrier between the first ring 1 and the second ring 2 can be provided. The sealing device using this sealing gasket is as shown in Figure 8 the figure.

[0045] Example 5

[0046] Refer to Figure 9 the gasket shown. The main difference between it and the gasket in Example 4 is that in this example, a first outer sealing ring 9 is further provided on the outer shaft end of the first ring 1. The first outer sealing ring 9 is located radially outside the first sealing ring 3. A first leak detection hole 13 penetrating axially is also provided on the first ring 1. The first leak detection hole 13 is located radially between the first sealing ring 3 and the first outer sealing ring 9. A second outer sealing ring 10 is further provided on the outer shaft end of the second ring 2. The second outer sealing ring 10 is located radially outside the second sealing ring 4. A second leak detection hole 22 penetrating axially is also provided on the second ring 2. The second leak detection hole 22 is located radially between the second sealing ring 4 and the second outer sealing ring 10. In this way, leakage detection and monitoring of the overall sealing condition can be carried out. The sealing device using this gasket is as Figure 10 shown.

[0047] The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. A sealing gasket, characterized in that: The sealing gasket includes a first ring and a second ring which are coaxially stacked. A first sealing ring is provided at the outer axial end of the first ring, and a second sealing ring is provided at the outer axial end of the second ring. The sealing gasket further includes a stress relief ring. The longitudinal section of the stress relief ring is in a C shape arched radially outward. A first arc-shaped groove is provided at the inner circumferential part of the first ring, and a second arc-shaped groove is provided at the inner circumferential part of the second ring. The first arc-shaped groove and the second arc-shaped groove cooperate with each other to form a receiving space for receiving the stress relief ring. The two axial ends of the stress relief ring are respectively welded and fixed to the first ring and the second ring along the circumferential direction, and the outer circumferential surface of the stress relief ring is arranged with a gap between the circumferential groove walls of the first arc-shaped groove.

2. The gasket according to claim 1, wherein: The gap between the outer circumferential surface of the stress relief ring and the circumferential groove walls of the first arc-shaped groove is arranged to gradually increase from outside to inside along the axial direction of the first ring.

3. The gasket according to claim 1, wherein: Among the inner axial ends of the first ring and the inner axial ends of the second ring, a ring-shaped boss is provided on one of them, and a ring-shaped groove is provided on the other. The radial thickness of the ring-shaped boss is less than the radial width of the ring-shaped groove, and the ring-shaped boss is correspondingly inserted into the ring-shaped groove.

4. The gasket according to claim 3, characterized in that: The ring-shaped boss is provided on the first ring, and the ring-shaped groove is provided on the second ring. The inner circumferential surface of the ring-shaped boss is arranged with a gap between the inner circumferential walls of the ring-shaped groove.

5. The gasket according to claim 3, characterized in that: The ring-shaped groove is provided on the first ring, and the ring-shaped boss is provided on the second ring. The outer circumferential surface of the ring-shaped boss is arranged with a gap between the outer circumferential walls of the ring-shaped groove.

6. The gasket according to claim 3, characterized in that: An inner sealing ring is further provided on the ring-shaped boss, and the inner sealing ring is sealingly connected to the bottom surface of the ring-shaped groove.

7. The gasket according to claim 1, wherein: The sealing gasket further includes a leak detection ring. The two axial ends of the leak detection ring are respectively welded and fixed to the outer circumferential part of the first ring and the outer circumferential part of the second ring along the circumferential direction. A closed leak detection chamber is formed among the first ring, the second ring, the stress relief ring and the leak detection ring. A leak guiding pipe communicating with the leak detection chamber is further connected to the leak detection ring. The longitudinal section of the leak detection ring is convex or concave radially.

8. The gasket according to claim 7, characterized in that: A first outer sealing ring is further provided at the outer axial end of the first ring. The first outer sealing ring is located radially outside the first sealing ring. A first leak detection hole penetrating axially is provided on the first ring. The first leak detection hole is located radially between the first sealing ring and the first outer sealing ring. A second outer sealing ring is provided at the outer axial end of the second ring. The second outer sealing ring is located radially outside the second sealing ring. A second leak detection hole penetrating axially is provided on the second ring. The second leak detection hole is located radially between the second sealing ring and the second outer sealing ring.

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